Comparison of measured biolipid PCB concentrations with those estimated from (a) KOW values, the sediment fOC, and solid phase concentrations according to eq 3; (b) solid phase concentrations, the sediment fOC, and fBC and KOW values according to equations (5 − 7); (c) the contaminant mass fraction desorbed from sediment using a tenax extraction according to eq 4; and (d) actual measured free aqueous concentrations according to eq 2. Data represent Hunters Point sediment, Neanthes arenaceodentata (⧫) and Leptocheirus plumulosus (◊); Grasse River sediment, Lumbriculus variegatus (◻); Crab Orchard Lake sediment, Lumbriculus variegatus (•); Milwaukee River location 1 sediment, Lumbriculus variegatus (Δ); Milwaukee River location 2 sediment, Lumbriculus variegatus (×); and Niagara River sediment, Lumbriculus variegatus (+). The line is drawn to show a 1:1 relationship between estimated and measured data.